1. Field of the Invention
The present invention relates to a wheel control state display apparatus for displaying control states of wheels.
2. Related Background Art
In recent years control of travel of vehicles has been becoming highly advanced and there are examples wherein the braking force and/or traction (which will also be referred to together as xe2x80x9ctraction-braking forcexe2x80x9d) at wheels is automatically adjusted by various systems mounted on vehicles. For example, such various systems include a traction control system intended to efficiently yield the traction while suppressing acceleration slip of the wheels, an ABS (anti-lock brake system) intended to efficiently obtain the braking force while suppressing deceleration slip of the wheels, a stability control system intended to stabilize vehicle motion, a brake assist system for compensating for shortage of braking force upon panic braking, and so on.
When these traction-braking force controls were active, a beeper or an indicator in a meter informed the driver of the active status of the traction-braking force controls (though there were also such cases that the driver was not informed of the control of the ABS etc.). Japanese Patent Application Laid-Open No. 3-182862 also describes a unit designed to detect the slip of each wheel and display which wheel is slipping.
In the conventional controls wherein the traction-braking force was adjusted automatically, the driver was not informed of which wheel was under control of the traction-braking force by the various control systems. As for the unit capable of displaying which wheel is slipping, it was able to display slipping states of the wheels, but it failed to indicate control activity of the traction-braking force. However, should the driver know which wheel is under control of the traction-braking force by the various control systems, the driver would be able to recognize the circumstances of the vehicle in more detail and drive the vehicle with reflecting the information in certain cases.
An object of the present invention is, therefore, to provide a wheel control state display apparatus that can display which wheel is under control of the traction-braking force, so as to present the state of the vehicle to the driver in detail.
A wheel control state display apparatus of the present invention comprises vehicle state detecting means for detecting a state of a vehicle; traction-braking force control means for adjusting braking force or traction at a plurality of wheels mounted on the vehicle, based on a result of detection of the vehicle state detecting means; and control state display means for displaying a wheel under adjustment of the braking force or the traction by the traction-braking force control means.
In the wheel control state display apparatus of the present invention, the control state display means displays the wheel under the adjustment of the traction-braking force during periods of the adjustment of the traction-braking force by the traction-braking force control means, based on the result of detection of the vehicle state detecting means, whereby the driver is allowed to recognize the state of the vehicle in detail.
In a preferred embodiment, the control state display means comprises display areas for the respective wheels located in a layout similar to that of the wheels in the vehicle. This structure clearly shows which wheel is under the adjustment of the traction-braking force executed by the traction-braking force control means, whereby the driver is allowed to recognize the indication readily even during driving.
In a further preferred embodiment, the traction-braking force control means comprises braking force adjusting means for adjusting the braking force at each of the wheels by urging a friction material against the wheel or a rotary part to which the wheel is coupled and the control state display means displays a wheel under adjustment of the braking force by the braking force adjusting means. This structure permits the driver to recognize that the xe2x80x9cbraking forcexe2x80x9d is adjusted by the braking force adjusting means, as well as the simple recognition of the adjustment of traction-braking force, whereby the driver is allowed to recognize the state of the vehicle in more detail.
In another preferred embodiment, similar to the above, the traction-braking force control means comprises traction adjusting means for adjusting the traction at the wheels and the control state display means displays a wheel under adjustment of the traction by the traction adjusting means. This structure permits the driver to recognize that the xe2x80x9ctractionxe2x80x9d is adjusted by the traction adjusting means, as well as the simple recognition of the adjustment of traction-braking force, whereby the driver is allowed to recognize the state of the vehicle in more detail.
In another preferred embodiment, the traction-braking force control means comprises braking force adjusting means for adjusting the braking force at each of the wheels by urging a friction material against the wheel or a rotary part to which the wheel is coupled, and traction adjusting means for adjusting the traction at the wheels, and the control state display means displays different display patterns in the display areas for the respective wheels between in a situation in which only the xe2x80x9cbraking forcexe2x80x9d is adjusted at the wheels by the braking force adjusting means and in a situation in which only the xe2x80x9ctractionxe2x80x9d is adjusted at the wheels by the traction adjusting means.
This structure allows the driver to recognize that the adjustment of the traction-braking force is effected either by the braking force adjusting means or by the traction adjusting means while discriminating one from another, as well as the simple recognition of the adjustment of the traction-braking force. When the control state display means displays the different display patterns, the driver can accurately recognize which is under way between the adjustment of the braking force by the braking force adjusting means and the adjustment of the traction by the traction adjusting means, even during driving.
In a further preferred embodiment, the vehicle state detecting means is slip rate detecting means for detecting slip rates of the wheels, and the traction-braking force control means is traction control means for adjusting the braking force or the traction at the wheels in order to restrain a slip at the wheels, based on a result of detection of the slip rate detecting means.
The present invention will be more fully understood from the detailed description given hereinbelow and the accompanying drawings, which are given by way of illustration only and are not to be considered as limiting the present invention.
Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will be apparent to those skilled in the art from this detailed description.